This invention relates to a suspension and drive arrangement for three wheel vehicles and more particularly to improvements in the suspension and driving arrangement for such vehicles that improve their utility and their stability in a wide variety of off the road applications.
Recently, the use of three wheel vehicles for off the road use has gained considerable popularity. Such vehicles are used for a wide variety of purposes including recreational purposes and are operated over a wide variety of terrains. Such vehicles initially did not employ any suspension system but merely relied upon their large balloon type, low pressure tires to afford some comfort for the operator. However, due to the wide variety of terrain over which these vehicles are operated and the extreme variations in grade, it has been proposed to employ a suspension system, particularly for the driven rear wheels to improve their stability and further add to their utility. Although in some regards these vehicles resemble motorcycles, the suspension and drive arrangement employed in conjunction with motorcycles are not particularly adaptable to three wheel vehicles due to the significant differences in their construction and the terrain over which they are operated.
It is, therefore, a principal object of this invention to provide an improved three wheel off the road vehicle.
It is another object of this invention to provide a suspension system for an off the road vehicle which will significantly add to the utility of the vehicle and its stability over widely varying terrains.
Although the advantages of employing a suspension system in three wheel vehicles has been well recognized, there has been some reluctance to incorporate a suspension system in this type of vehicle. One difficulty in conjunction with the provision of a suspension system for a vehicle of this nature is that the extreme compact nature of the vehicle makes the use of conventional suspension systems employed with pairs of driven wheels not applicable or unsatisfactory. That is, although the rear axle and driving arrangement of such off the road three wheel vehicles generally resembles the driving arrangement of an automobile having a live rear axle, automotive type suspension systems are not particularly adaptable to use in three wheel vehicles. Even compact automobiles have relatively large spaces available for the suspension components and can provide for substantial amounts of suspension travel with conventional suspension arrangements. With an off the road vehicle, it is particular important to provide a suspension system that permits wide degrees of suspension travel due to the wide varieties and types of terrains over which the vehicle is operated. However, the extremely compact nature of these vehicles has, heretofore, made such large suspension travels unobtainable.
It is, therefore, a still further object of this invention to provide a suspension system for a three wheel vehicle that accommodates substantial suspension travel without increasing the size of the vehicle.
It is another object of this invention to provide an improved, compact suspension system for a three wheel vehicle that permits large suspension movements.
Due to the wide varieties of usage to which off the road three wheel vehicles are put, it is desirable to provide a transmission system having a plurality of ratios for such vehicles. The use of transmission systems obviously adds to the utility of the vehicle. However, when a suspension system is employed for the driven wheels, it is extremely difficult to provide a multi-speed transmission.
It is, therefore, a still further object of this invention to provide a compact, highly effective multi-speed transmission and drive arrangement for a three wheel vehicle.
It is another object of this invention to provide an improved suspension drive and transmission arrangement for a three wheel vehicle that permits suspension movement of the driven wheels.
Due to the compact nature of off the road three wheel vehicles, it has been normally the practice to drive the rear wheels by means of either a drive shaft or a driving chain that is offset from the center line of the vehicle. With such an arrangement and considering the compact nature of these vehicles, such offset drives tend to provide unbalance in the driving and suspension arrangement of the vehicle. That is, the offset of the driving mechanism to one side of the vehicle tends to unbalance the weight of the vehicle and can provide unsatisfactory ride.
It is, therefore, still another object of this invention to provide an improved driving and suspension arrangement for a three wheel vehicle that improves stability.
It is another object of this invention to provide a suspension and drive arrangement for a compact three wheel vehicle in which the suspension system compensates for the offset of the drive arrangement.
In suspension systems for driven live axles carrying pairs of wheels, such as automotive applications, it has been the common practice to provide a suspension element consisting of a spring and/or shock absorber at each side of the axle contiguous to the respective driven wheel. Although such arrangements maybe be used in conjunction with three wheel vehicles, as aforenoted, the compact nature of these vehicles does not always permit the use of such suspension systems. It has been found practical to employ a single suspension element for the rear wheels of off the road three wheel vehicles in lieu of the pairs of suspension elements used in conventional automotive type suspension systems. However, when such an arrangement is employed, the element that carries the wheel and which transmits the load to the suspension element must be sufficiently strong so as to insure against breakage. One form of suspension system employed for such vehicles employs a trailing arm for suspending the rear axle. If the trailing arm is used to load the suspension element, it must be of sufficient strength so as to insure against breakage, considering particularly the extreme usage to which such vehicles are put.
It is, therefore, a further object of this invention to provide an improved trailing arm construction for three wheel vehicles.
Because of the compact nature of off the road three wheel vehicles of the type described, it has been found necessary in some instances to employ an arrangement wherein additional loads may be carried by such vehicles. Although various carriers have been proposed for such vehicles, they do not always provide sufficient capacity or optimum utility for load carrying purposes. It has, therefore, been proposed to employ the use of trailers with such vehicles. However, due to the wide variety of terrain over which such vehicles are operated, previously proposed trailer hitches have not been particularly satisfactory due to the wide variety of loadings which they can impose upon the suspension system of the vehicle.
It is, therefore, a further object of this invention to provide an improved trailer hitch arrangement for an off the road three wheel vehicle that does not affect the suspension system of the vehicle.